Unstudied Items Research Articles

Associative asymmetry of the recognition without cued-recall effect in thematic relations

ABSTRACT In the present study, two experiments were conducted to examine whether thematic relation can produce recognition without cued-recall effect and whether the direction of the association has an influence on this effect. The participants provided higher familiarity ratings for studied items than for unstudied items during target retrieval failure. Additionally, the thematic relation-elicited recognition without cued-recall effect was larger in the forward association than in the backward association. Collectively, these results indicated that thematic relations can elicit the recognition without cued-recall effect, and this effect is asymmetrical. The current findings support the features overlap hypothesis described in the global match model.

Pupil size tracks cue-trace interactions during episodic memory retrieval.

Our ability to remember past events requires not only storing enduring engrams or memory traces of these events, but also successfully reactivating these latent traces in response to appropriate cues at the time of retrieval-a process that has been termed ecphory. However, relatively little is known about the processes that facilitate the dynamic interactions between retrieval cues and stored memory traces that are critical for successful recognition and recollection. Recently, an intriguing link between pupil dilation and recognition memory has been identified, with studied items eliciting greater pupil dilation than unstudied items during retrieval. However, the processes contributing to this "pupillary old/new effect" remain unresolved, with current explanations suggesting that it reflects the strength of the underlying memory trace. Here, we explore the novel hypothesis that the pupillary old/new effect does not index memory strength alone, but rather reflects the facilitation of cue-trace interactions during episodic memory retrieval that may be supported by activity within the pupil-linked locus coeruleus-noradrenergic (LC-NA) arousal system. First, we show that the magnitude of pupil dilation is influenced by the degree of overlap between cue and trace information. Second, we find that the magnitude of pupil dilation reflects the amount of study contextual information reinstated during retrieval. These findings provide a novel framework for understanding the pupillary old/new effect, and identify a potential role for the LC-NA system in recognition memory retrieval.

Cue overlap supports preretrieval selection in episodic memory: ERP evidence

People often want to recall events of a particular kind, but this selective remembering is not always possible. We contrasted two candidate mechanisms: the overlap between retrieval cues and stored memory traces, and the ease of recollection. In two preregistered experiments (Ns = 28), we used event-related potentials (ERPs) to quantify selection occurring before retrieval and the goal states — retrieval orientations — thought to achieve this selection. Participants viewed object pictures or heard object names, and one of these sources was designated as targets in each memory test. We manipulated cue overlap by probing memory with visual names (Experiment 1) or line drawings (Experiment 2). Results revealed that regardless of which source was targeted, the left parietal ERP effect indexing recollection was selective when test cues overlapped more with the targeted than non-targeted information, despite consistently better memory for pictures. ERPs for unstudied items also were more positive-going when cue overlap was high, suggesting that engagement of retrieval orientations reflected availability of external cues matching the targeted source. The data support the view that selection can act before recollection if there is sufficient overlap between retrieval cues and targeted versus competing memory traces.

Feeling the ease: How the use of oral motor fluency changes in amnesia.

The present study examined the evolution observed in amnesic patients' use of motor fluency when making recognition memory decisions. In this experiment, 9 patients with amnesia and 18 matched controls were presented with two recognition memory tasks composed of 3 types of items: (1) natural words, (2) nonwords difficult to pronounce, and (3) nonwords easy to pronounce, the latter having been shown to be processed in a surprisingly fluent manner as long as participants can articulate them at a subvocal level (i.e., oral motor fluency). Our results provide evidence that the motor-movement manipulation was successful to induce a fluency effect. More specifically, data revealed that both amnesic patients and control participants showed a pattern of response consistent with the use of fluency as a cue to memory for studied items. However, only control participants relied on fluency to increase their rate of "yes" responses for unstudied items. These results suggest that patients with amnesia set a more conservative response criterion before relying on oral motor fluency, showing a pattern consistent with the idea that fluency is only used as a cue to memory when it exceeds a certain threshold. These findings are discussed in terms of adaptative metacognition strategies implemented by amnesic patients to reduce fluency-based memory errors as well as in terms of the variations that seem to occur in these strategies depending on the type of fluency that is experienced.

Age of acquisition effects in recognition without identification tasks

ABSTRACT The Age of Acquisition (AoA) effect results in early-acquired words being processed more quickly and accurately than later-acquired words. This effect is argued to result from a gradual development of semantic representations and a changing neural network throughout development (Chang, Y.-N., Monaghan, P., & Welbourne, S., 2019). Some forms of the Recognition Without Identification (RWI) effects have been observed at a perceptual level. The present study used the RWI paradigm to examine whether the AoA effect is located at the perceptual loci. A total of 174 participants were presented a list of pictures (Experiment 1) or words (Experiment 2) followed by a list of mixed early- and late-acquired picture or word fragments that participants had to identify; half of which corresponded to studied words and half of which to unstudied words. Irrespective of whether the item was identified, participants then rated the likelihood that the item appeared in the study phase. In both experiments, results showed that studied items were recognised more accurately than unstudied items, even when they could not be identified and late-acquired items were recognised more than early-acquired items, even when they were not identified. Finally, RWI interacted with the AoA effect only in pictorial stimuli, suggesting that the RWI and AoA effects are located at the perceptual level.

Reversible Verbal Memory Integration Deficits in Obstructive Sleep Apnoea.

When presented with novel but semantically related elements after learning verbal material, healthy participants tend to endorse these items as previously learned. This reflects the normal integration and association of novel verbal information into long-term memory. How obstructive sleep apnoea (OSA) negatively impacts verbal memory performance, and whether deficits are reversible following positive airway pressure (PAP) treatment, remain elusive. We investigated immediate and delayed OSA- and PAP treatment-related effects on verbal memory integration, using a false memory paradigm. Twenty-three patients with OSA learned lists of words semantically related to target non-presented words (1) at baseline after a polysomnography diagnosis night, (2) after a consecutive polysomnography night under PAP titration, and (3) after three months of compliant PAP treatment. At each session, participants learned 10 different lists of words, each list comprising 15 semantically related items. They had then to recognize 15 minutes later (after an intermediate vigilance task) previously learned words within a list including studied words (learned), unstudied but semantically related items (lures), and non-related unstudied items (controls). Sleep quality and fatigue questionnaires, and psychomotor vigilance tests (PVT) were administered at each session. PAP treatment led to OSA remission and improvement in objective and subjective sleep quality. Crucially, recognition of learned and lure words increased after the first night under treatment and remained stable three months later, suggesting successful memory integration and restoration of semantic processes. No treatment-related outcome was found on PVT performance. OSA exerts a detrimental but PAP-reversible effect on verbal learning and semantic memory integration mechanisms underlying the acquisition of novel memory representations.

Context influences the FN400 recognition event-related potential

Recognition of studied items often elicit more positive event-related potentials (ERPs) than unstudied items at mid-frontal electrodes about 300–500 ms (i.e., the FN400). The debate over the psychological processes associated with the FN400 has led to two competing hypotheses. One hypothesis is that the FN400 reflects familiarity, whereas another hypothesis is that it reflects conceptual implicit memory (i.e., conceptual fluency). The present experiment tested these hypotheses by presenting meaningless images that lack familiarity and conceptual fluency, off-brand products that lack pre-experimental familiarity, and name-brand products that have both pre-experimental familiarity and conceptual fluency. ERPs were recorded during judgments of lifetime and recent recognition. During both forms of recognition, ERPs in the FN400 window were greater for meaningless images than name- or off-brand products. Because this evidence is difficult to reconcile with either the familiarity or conceptual fluency hypotheses, the results are interpreted within a broader theoretical framework that includes top-down psychological (i.e., context) influences on the FN400.

False memory for faces is produced by the Deese-Roediger-McDermott paradigm based on the morphological characteristics of a list

Previous studies on false memory of non-semantic stimuli reported that false memories were produced for items that were unstudied but that were similar to the studied items. However, it remains unclear what representations of false memory are constructed by studied items and how the representations of studied items contribute to the occurrence of false memory. Therefore, we examined whether false memory is produced in the Deese-Roediger-McDermott (DRM) paradigm for non-semantic stimuli (i.e., facial lists), which was divided according to the morphological characteristics quantified by principal component analysis, and whether the false memory rate could be quantitatively predicted by the morphological characteristics of the studied items with a regression analysis. Thirty-five participants memorized five faces and performed a recognition memory test, including an unstudied lure item whose morphological characteristics were approximately the average of the studied items. The results showed that the lure items were more likely to be falsely remembered than other unstudied items whose morphological characteristics were not the average of the studied items, indicating that false memory of non-semantic stimuli was produced in the DRM paradigm owing to the morphological characteristics of the studied items. In contrast, the false memory rate could not be quantitatively explained by each kind of morphological characteristic. This indicates that false memory was not caused by the particular morphological characteristic of the studied items. Moreover, these results implicate that false memory of non-semantic stimuli in the DRM paradigm was provoked by gist representation of the studied items.

Does Test Type Influence False Recognition in the DRM Paradigm? Comparison of the Yes/No Recognition Test and Two-Alternative Forced-Choice Test

Abstract Studies attempting to identify the mechanisms that are responsible for the level of false recognition in the DRM paradigm usually apply a manipulation during encoding. The main aim of the studies reported here was to investigate the within- and between-participant effects of a testing method on memory performance using a standard yes/no recognition test and a 2-alternative forced-choice recognition test (2FC). To allow a direct comparison of the 2 testing methods, a 2FC test containing similar items as a typical yes/no test in the DRM paradigm was elaborated on in the pilot study. Moreover, 2 methods of data calculation were used: comparing rates of hit and false alarms with critical lures and with unstudied and unrelated items between the 2 tests and comparing measures of sensitivity (d’) derived from signal detection theory. Both experiments showed a lower false alarm rate to critical lures and higher hit rate in a 2FC test as compared with a yes/no test, depicting a typical mirror effect. A within-participant design (Experiment 1) also showed that this increased accuracy of a 2FC test diminished when memory performance was expressed in terms of a sensitivity measure, which may suggest that similar processes are used during these 2 retrieval methods. A similar analysis performed for a between-participants design (Experiment 2) revealed that a 2FC test was less susceptible to associative memory distortions, but the quality of memory (“remember/know” judgments) remained similar for both tests.

The congruent, the incongruent, and the unexpected: Event-related potentials unveil the processes involved in schematic encoding

Learning is most effective when new information can be related to a preexisting knowledge structure or schema. In the present study, event-related potentials (ERPs) were used to investigate the temporal dynamics of the processes by which activated schemata support the encoding of schema-congruent information. Participants learned category exemplar words that were either semantically congruent or incongruent with a preceding category cue phrase. Congruent words were composed of expected (high typicality, HT) and unexpected (low typicality, LT) category exemplars. On the next day, recognition memory for the exemplars and the category cues they were presented with was tested. Semantically related lures were used in order to ascertain that memory judgements were based on episodic memory for specific category exemplars. Generally, congruent (HT and LT) exemplars were remembered better than incongruent exemplars. ERPs recorded during the encoding of the exemplar words were compared for subsequently remembered and forgotten items. Subsequent memory effects (SME) emerged in the N400 time window at frontal electrodes and did not differ between congruent and incongruent exemplars. In the same epoch, an SME with a parietal distribution was specific for congruent exemplars, suggesting that activated schemata strengthened memory for congruent exemplars by supporting the encoding of item-specific details. Subsequently remembered LT exemplars were associated with a late frontal positivity that is assumed to reflect expectancy mismatch-related processing such as the contextual integration of an unexpected word by the suppression of strongly expected words. A correlation analysis revealed that the greater the involvement of the processes reflected by the frontal positivity, the lower the level of false positive memory responses in the test phase one day later. These results suggest that the contextual integration of schema-congruent but unexpected events involves a weakening of the representations of semantically related, but unstudied items in memory and by this benefits subsequent memory.

Story Time: Essays on the Betsy Beinecke Shirley Collection of American Children's Literature ed. by Timothy Young

Reviewed by: Story Time: Essays on the Betsy Beinecke Shirley Collection of American Children's Literature ed. by Timothy Young Courtney Weikle-Mills Story Time: Essays on the Betsy Beinecke Shirley Collection of American Children's Literature. Edited by Timothy Young. New Haven: Yale University Press, 2016. 280 pp. Paper $30. The subject of this volume, published by the Beinecke Rare Book and Manuscript Library at Yale University, is the wealth of American storybooks and manuscript materials for children housed in the library's Betsy Beinecke Shirley [End Page 126] collection. Fitting to its title, the sumptuous book, which features fifteen essays and seventy-one images from published and unpublished children's works, is a truly delightful "story time" in itself. Its pages contain tales of dueling librarians and authors; collaborations between writers not best known for children's literature (namely Langston Hughes and Arna Bontemps); immigrants becoming illustrators; and even "wayward animals," llamas who intrude into Karl Marx's famous analysis of Robinson Crusoe via an illustrated adaptation (79). Underneath these stories are implicit ones—about the importance of one dedicated collector, Shirley, and about the thrill of discovery in the archives (this reader would have loved to have been with Jill Campbell when she discovered the source of those llamas!). Unsurprisingly, the pieces, all written by contributors who spent time at the Beinecke, are impeccably researched. Several bring to light unstudied items, demonstrating their connection to key developments in American children's literature. For instance, Elizabeth Frengel suggests that the artist's dummies for Ludwig Bemelmans' Castle No. 9 (1936) display an early use of the concept Maurice Sendak would later call "counterpoint," the technique recognized by scholars as the hallmark of the modern picture book (49). Laura Wasowicz, curator of children's literature at the American Antiquarian Society, mines Shirley's "significant cache of picture book artwork" from the behemoth nineteenth-century publisher, the McLoughlin Brothers, to uncover some of the earliest American illustrators to be credited for their work (173). A running theme in essays by JoAnn Conrad, Pádraic Whyte, and Brian Alderson is the seminal work done by immigrants in the development of American publishing and especially illustration, which, as these scholars point out, built upon the taste of powerful Brooklyn librarian Anne Carroll Moore and Horn Book creator Bertha E. Mahony for fantastical stories. The essays attend to milestones so thoroughly that the collection could be used to support a survey for undergraduates. Essays cover a historical range from Puritan "joyful death stories" (Timothy Young) to classic picture books like Blueberries for Sal (Katie Trumpener) and Mo Willems's satires of modern parenting (Heather Klemann). Martin's essay on Hughes and Bontemps outlines the emergence of modern African American children's literature through the making of one book, Popo and Fifina (1932), with robust attention to context. I can also see the volume being well suited for graduate students, in that it models strong research and writing. Though Young's introduction does not assert a unifying intellectual contribution for the volume, choosing rather to emphasize the productivity of the essays' multiple approaches, the pieces taken together make a compelling statement about how children's literature involves a host of collaborators, including authors, illustrators, publishers, educators, librarians, and, of course, collectors. [End Page 127] The volume also makes an implicit case that children's literature scholarship is, at its best, an interdisciplinary endeavor, including archivists and authors, as well as scholars. Four of the essays are by curators at the Beinecke and elsewhere, and the contributors also include author Gregory Maguire and writer/publisher Patrick Kiley. This implicit endorsement of interdisciplinarity is significant because, as Beverly Lyon Clark (whose essay in this volume traces the illustrations of Louisa May Alcott's Little Women) has argued in Kiddie Lit, children's literature scholarship has sometimes divorced itself from the work of librarians and authors in order to make the case for its objectivity as a field. Yet the interrelationships that shape the world of children's literature are now emerging as an exciting focus of scholarship. Leonard S. Marcus's piece stands out in this regard, outlining how Bank Street educator Lucy Sprague Mitchell, publisher...

Inferior parietal transcranial direct current stimulation with training improves cognition in anomic Alzheimer's disease and frontotemporal dementia

IntroductionWe evaluated whether transcranial direct current stimulation (tDCS) can improve picture-naming abilities in subjects with anomic Alzheimer or frontotemporal dementias. MethodsUsing a double-blind crossover design, 10 participants were trained on picture naming over a series of 10 sessions with either 30 minutes of anodal (2 mA) tDCS stimulation to the left inferior parieto-temporal region (P3) or sham stimulation. We evaluated performance on a trained picture-naming list, an equivalent untrained list, and additional neuropsychological tasks. ResultsParticipants improved significantly more receiving real stimulation rather than sham stimulation (40% vs. 19%, P < .01), lasting at least 2 weeks after stimulation. Furthermore, these participants showed a small increase for untrained picture-naming items and digit span when they received real stimulation but a decrease when sham stimulation was received. DiscussiontDCS stimulation has promise as a treatment for anomia in demented individuals and the effect can generalize to unstudied items as well as other cognitive abilities.

Reduced effects of pictorial distinctiveness on false memory following dynamic visual noise

ABSTRACTHigh levels of false recognition for non-presented items typically occur following exposure to lists of associated words. These false recognition effects can be reduced by making the studied items more distinctive by the presentation of pictures during encoding. One explanation of this is that during recognition, participants expect or attempt to retrieve distinctive pictorial information in order to evaluate the study status of the test item. If this involves the retrieval and use of visual imagery, then interfering with imagery processing should reduce the effectiveness of pictorial information in false memory reduction. In the current experiment, visual-imagery processing was disrupted at retrieval by the use of dynamic visual noise (DVN). It was found that effects of DVN dissociated true from false memory. Memory for studied words was not influenced by the presence of an interfering noise field. However, false memory was increased and the effects of picture-induced distinctiveness was eliminated. DVN also increased false recollection and remember responses to unstudied items.

Neural Global Pattern Similarity Underlies True and False Memories.

The neural processes giving rise to human memory strength signals remain poorly understood. Inspired by formal computational models that posit a central role of global matching in memory strength, we tested a novel hypothesis that the strengths of both true and false memories arise from the global similarity of an item's neural activation pattern during retrieval to that of all the studied items during encoding (i.e., the encoding-retrieval neural global pattern similarity [ER-nGPS]). We revealed multiple ER-nGPS signals that carried distinct information and contributed differentially to true and false memories: Whereas the ER-nGPS in the parietal regions reflected semantic similarity and was scaled with the recognition strengths of both true and false memories, ER-nGPS in the visual cortex contributed solely to true memory. Moreover, ER-nGPS differences between the parietal and visual cortices were correlated with frontal monitoring processes. By combining computational and neuroimaging approaches, our results advance a mechanistic understanding of memory strength in recognition. What neural processes give rise to memory strength signals, and lead to our conscious feelings of familiarity? Using fMRI, we found that the memory strength of a given item depends not only on how it was encoded during learning, but also on the similarity of its neural representation with other studied items. The global neural matching signal, mainly in the parietal lobule, could account for the memory strengths of both studied and unstudied items. Interestingly, a different global matching signal, originated from the visual cortex, could distinguish true from false memories. The findings reveal multiple neural mechanisms underlying the memory strengths of events registered in the brain.

Electrophysiological evidence for flexible goal-directed cue processing during episodic retrieval

A widely held assumption is that memory retrieval is aided by cognitive control processes that are engaged flexibly in service of memory retrieval and memory decisions. While there is some empirical support for this view, a notable exception is the absence of evidence for the flexible use of retrieval control in functional neuroimaging experiments requiring frequent switches between tasks with different cognitive demands. This absence is troublesome in so far as frequent switches between tasks mimic some of the challenges that are typically placed on memory outside the laboratory. In this experiment we instructed participants to alternate frequently between three episodic memory tasks requiring item recognition or retrieval of one of two different kinds of contextual information encoded in a prior study phase (screen location or encoding task). Event-related potentials (ERPs) elicited by unstudied items in the two tasks requiring retrieval of study context were reliably different, demonstrating for the first time that ERPs index task-specific processing of retrieval cues when retrieval goals change frequently. The inclusion of the item recognition task was a novel and important addition in this study, because only the ERPs elicited by unstudied items in one of the two context conditions diverged from those in the item recognition condition. This outcome constrains functional interpretations of the differences that emerged between the two context conditions and emphasises the utility of this baseline in functional imaging studies of retrieval processing operations.

Electrophysiological correlates associated with contributions of perceptual and conceptual fluency to familiarity.

The present research manipulated the fluency of unstudied items using masked repetition priming procedures during an explicit recognition test. Based on fluency-attribution accounts, which posit that familiarity can be driven by multiple forms of fluency, the relationship between masked priming-induced fluency and familiarity was investigated. We classified pictographic characters into High-Meaningfulness (High-M) and Low-Meaningfulness (Low-M) categories on the basis of subjective meaningfulness ratings and identified the distinct electrophysiological correlates of perceptual and conceptual fluency. The two types of fluency differed in associated ERP effects: 150–250 ms effects for perceptual fluency and FN400 effects for conceptual fluency. The ERPs of Low-M MP-same (items that were preceded by matching masked items) false alarms were more positive than correct rejections during 150–250 ms, whereas the ERPs of High-M MP-same false alarms were more positive than correct rejections during 300–500 ms. The topographic patterns of FN400 effects between High-M MP-same false alarms and Low-M MP-same false alarms were not different from those of High-M hits and Low-M hits. These results indicate that both forms of fluency can contribute to familiarity, and the neural correlates of conceptual fluency are not different from those of conceptual priming induced by prior study-phase exposure. We conclude that multiple neural signals potentially contribute to recognition memory, such as numerous forms of fluency differing in terms of their time courses.

Lateral posterior parietal activity during reality monitoring discriminations of memories of high and low perceptual vividness.

Regions of the lateral posterior parietal cortex (PPC) tend to be more active during recognition of previously studied items compared to correct rejection of unstudied items. Previously, we demonstrated that this effect is source-specific. While items that were encoded through visual perception elicited robust successful retrieval activity in the lateral PPC during a subsequent source memory test, items that were visually imagined did not elicit this effect. Memories of perceived events typically contain more perceptually-based contextual details than memories of imagined events. Therefore, source-based differences in lateral parietal activity might be due to a difference in the perceptual vividness of memories of perceived and imagined events. The goal of the present study was to test this hypothesis. Participants perceived and imagined items in both high and low perceptual vividness conditions. Experiment 1 demonstrated that memories for items encoded in the high vividness conditions contained significantly greater visual detail than memories encoded in the low vividness conditions. In Experiment 2, participants were scanned while they made source memory judgments about items that were previously perceived and imagined in high and low vividness conditions. Consistent with previous findings, the left lateral PPC was more active during retrieval of perceived compared to imagined events. However, lateral PPC activity did not vary according to vividness, suggesting that source effects in this region cannot be explained by a difference in the perceptual vividness of memories encoded through perception versus imagination.

The temporal dynamics of visual object priming

Priming reflects an important means of learning that is mediated by implicit memory. Importantly, priming occurs for previously viewed objects (item-specific priming) and their category relatives (category-wide priming). Two distinct neural mechanisms are known to mediate priming, including the sharpening of a neural object representation and the retrieval of stimulus–response mappings. Here, we investigated whether the relationship between these neural mechanisms could help explain why item-specific priming generates faster responses than category-wide priming. Participants studied pictures of everyday objects, and then performed a difficult picture identification task while we recorded event-related potentials (ERP). The identification task gradually revealed random line segments of previously viewed items (Studied), category exemplars of previously viewed items (Exemplar), and items that were not previously viewed (Unstudied). Studied items were identified sooner than Unstudied items, showing evidence of item-specific priming, and importantly Exemplar items were also identified sooner than Unstudied items, showing evidence of category-wide priming. Early activity showed sustained neural suppression of parietal activity for both types of priming. However, these neural suppression effects may have stemmed from distinct processes because while category-wide neural suppression was correlated with priming behavior, item-specific neural suppression was not. Late activity, examined with response-locked ERPs, showed additional processes related to item-specific priming including neural suppression in occipital areas and parietal activity that was correlated with behavior. Together, we conclude that item-specific and category-wide priming are mediated by separate, parallel neural mechanisms in the context of the current paradigm. Temporal differences in behavior are determined by the timecourses of these distinct processes.

Positive and Negative Correlations Between Confidence and Accuracy for the Same Events in Recognition of Categorized Lists

Different researchers have reported positive, null, and negative relationships between confidence and accuracy in reports from memory. One possible reason for this paradox is the variety of materials used across experiments, but the two experiments reported in this article show that positive and negative confidence-accuracy correlations can be observed using a single procedure and the same materials. Subjects studied words from semantic categories and then took a recognition test while making confidence ratings. For previously studied items, positive correlations between confidence and accuracy were obtained using three different measures. Yet when confidence-accuracy correlations were assessed for unstudied items from studied categories, the correlations were zero or negative. The critical factors in determining when negative correlations will be found are the similarity of lures to presented items and the type of analysis used. These results indicate that one should be cautious about relying on confidence of recognition when rememberers must decide among highly similar events.

Investigating the subjective reports of rejection processes in the word frequency mirror effect

We sought to systematically investigate how participants subjectively classify the basis of their recognition memory judgments for low and high word frequency items. We found that participants more often reported rejection processes related to the increased perceived memorability for unstudied low word frequency items (relative to high word frequency items), rather than classifying their decision on a lack of familiarity. Experiment 2 replicated this pattern and demonstrated context variability and word frequency independently influenced the subjective classifications for correct rejections. Results of Experiment 3 revealed that these differences are dependent upon having experience with both low and high frequency items. Overall, these data suggest participants' rejection of low frequency items is more strongly related to judgments of perceived memorability, but only when they are presented in the context of high frequency items. The results are discussed in relation to distinctiveness and expected memorability.